Unlike ordinary Tears these are a genetic trait handed down from Fwayli to her many children. As the Great Dragon of Passion she was known for her strong feelings both good and il and in the rarest occasions she was said to cry liquid flame. This trait was passed down and has been recorded less than a hand full times. All vaelon who's cried Fwayli's Tears have been at an emotional apex of negativity.
Upon the death of Ellaria, Michael recalled "Though is eyes were vacant, tears ran that charred his clothing and turned the sands to glass". Even when he noticed Michael and his expression turned to Hell-Forge rage, he was still crying which could indicate that the tears are not the body crying but the soul.